The invention relates generally to levels of the type used by carpenters, masons and the like, and is particularly directed to a new and improved level vial assembly and a method for assembling the level vial assembly on a level body.
A primary object of the invention is to provide a level vial assembly that lends itself to automatic assembly with high accuracy, thus providing high quality at minimum cost.
Another object of the invention is to provide a level having an improved vial that is precision mounted in the level body in a facile manner.
Another object of the invention is to provide a pair of bezel-lens subassemblies which are designed for automatic precision mounting on opposite sides of a vial to protect and/or retain the vial.
Yet another object of the invention is to provide a curved level vial that is precision-molded in an efficient manner.
Another object of the invention is to provide a level vial assembly having a bezel-lens subassembly that is replaceable by the user, thereby eliminating the necessity of sending the level to the manufacturer to make this type of repair.
A further object of the invention is to provide a novel method of assembling a level vial assembly on a level body.
Other features and advantages of the invention will be in part obvious and in part pointed out more in detail hereinafter.
The invention in a preferred form is a level vial assembly for use in a carpenter's or mason's level. The assembly is configured for insertion into an aperture which extends through the level body in a direction perpendicular to the length of the working surface of the level. The assembly includes a vial holding plate which is sized to fit within the level body aperture and is supported within the aperture, preferably by adhesion to a shoulder or other stop means formed around the perimeter of the aperture. The holding plate has an opening which defines a pair of oppositely-directed notches for supporting a level vial in order to fix the longitudinal position of the vial and to angularly orient the vial at a preselected relationship relative to the working surface. The vial, which is designed to be placed between the notches, includes a tubular portion having constant inner and outer diameters, and is curved slightly along its longitudinal dimension. The vial preferably is molded, and in order to allow for efficient production, has a curved parting line extending longitudinally along opposite sides of the vial. The vial is properly positioned in the holding plate by at least one vial mounting tab which extends tangentially outward from the side wall of the vial proximate a longitudinal end of the vial. Preferably, the inner wall of the mounting tab bears against one side of the holding plate, proximate one of the notches, when the vial is oriented in a working position relative to the central plane of the holding plate. The mounting tab keeps the vial from being laterally displaced out of the plane of the holding plate on the side of the holding plate opposite to the mounting tab.
The level vial assembly further includes at least one bezel-lens subassembly which is mountable in the aperture on one side of the vial holding plate in order to cover and protect the vial. The subassembly includes a lens through which the vial can be viewed by the user. The lens is supported in a gasket or bezel which is sized to fit within the aperture. The bezel-lens subassembly is mountable proximate the tabbed side of the vial and includes means for limiting lateral movement of the vial relative to the holding plate in a direction toward the tabbed side of the vial. The vial support means preferably is a skirt portion having a semicircular indentation for supporting the vial along one side. The skirt prevents the vial from being laterally displaced out of the holding plate on the side of the holding plate which is in contact with the mounting tab. Preferably, the vial is protected by a bezel-lens subassembly on each of two opposite sides, and each subassembly has vial support means defined by a skirt which contacts the sides of the vial near its ends. The skirt contributes to the aesthetics of the level by shielding the ends of the vial from the user's view.
The invention further includes a novel method for assembling a level vial assembly on a level body having an aperture for receiving the assembly. The method comprises mounting a vial holding plate in the aperture so that a portion of the holding plate abuts a stop means in the aperture. The holding plate includes an opening having a vial mounted therein. The vial includes a tubular portion having longitudinally spaced ends and an outer side wall having at least one tangentially extending tab for limiting lateral movement of the vial in a first direction perpendicular to the plane of the alignment plate. The method further comprises mounting a bezel lens subassembly in the aperture on the tabbed side of the vial. The bezel lens subassembly limits lateral movement of the vial in a second direction opposite to the first direction. Preferably, a second bezel-lens subassembly is mounted on the untabbed side of the vial to cover and protect that side of the vial.
The invention accordingly consists in the features of construction, combination of elements, arrangement of parts and the several steps of assembly, in relation to each other, which will be exemplified in the following detailed disclosure.